device-manager: skip graphical renderer setup when details forced

If neither "rhgb" nor "splash" is on the kernel cmdline, then
plymouth forces the "details" splash. This splash is merely
a passthrough plugin, where it makes boot looks like plymouth
isn't even running.

In this case, the code sets PLY_DEVICE_MANAGER_FLAGS_IGNORE_UDEV.
The idea is to not bother waiting for udev events notifying
plymouth when graphics devices show up, since it doesn't need
to use the grpahics devices directly anyway.

Unfortunately, it does still erroneously try to setup graphical
renderers in this case, including the /dev/fb renderer.

Before commit e4f86e3c, these graphical renderers failed because
they were given the wrong device name, but since that fix, they're
suceeding.  We definitely don't want the /dev/fb renderer to
load if we're ignoring udev on efi systems, since during very
early boot /dev/fb is backed by efifb, something we never want to
use.  efifb is supposed to get replaced during the boot process
by other fb implementations like say radeondrmfb, virtiodrmfb or
bochsdrmfb, and some of those implementations can't handle the
transition if /dev/fb is open at switchover time.

This commit adds a new flag to tell the device manager to
not bother trying to setup graphical renderers when details are
forced.

http://bugzilla.redhat.com/1518464

3 files changed, 21 insertions, 6 deletions

diff --git a/src/libply-splash-core/ply-device-manager.c b/src/libply-splash-core/ply-device-manager.c
index fbf4723b..b637fb8e 100644
--- a/src/libply-splash-core/ply-device-manager.c
+++ b/src/libply-splash-core/ply-device-manager.c
@@ -786,6 +786,15 @@ create_devices_from_terminals (ply_device_manager_t *manager)
         return false;
 }
 
+static void
+create_non_graphical_devices (ply_device_manager_t *manager)
+{
+        create_devices_for_terminal_and_renderer_type (manager,
+                                                       NULL,
+                                                       manager->local_console_terminal,
+                                                       PLY_RENDERER_TYPE_NONE);
+}
+
 #ifdef HAVE_UDEV
 static void
 create_devices_from_udev (ply_device_manager_t *manager)
@@ -801,10 +810,7 @@ create_devices_from_udev (ply_device_manager_t *manager)
                 return;
 
         ply_trace ("Creating non-graphical devices, since there's no suitable graphics hardware");
-        create_devices_for_terminal_and_renderer_type (manager,
-                                                       NULL,
-                                                       manager->local_console_terminal,
-                                                       PLY_RENDERER_TYPE_NONE);
+        create_non_graphical_devices (manager);
 }
 #endif
 
@@ -845,6 +851,12 @@ ply_device_manager_watch_devices (ply_device_manager_t                *manager,
         if (done_with_initial_devices_setup)
                 return;
 
+        if ((manager->flags & PLY_DEVICE_MANAGER_FLAGS_SKIP_RENDERERS)) {
+                ply_trace ("Creating non-graphical devices, since renderers are being explicitly skipped");
+                create_non_graphical_devices (manager);
+                return;
+        }
+
         if ((manager->flags & PLY_DEVICE_MANAGER_FLAGS_IGNORE_UDEV)) {
                 ply_trace ("udev support disabled, creating fallback devices");
                 create_fallback_devices (manager);
diff --git a/src/libply-splash-core/ply-device-manager.h b/src/libply-splash-core/ply-device-manager.h
index 058f6e86..ad058971 100644
--- a/src/libply-splash-core/ply-device-manager.h
+++ b/src/libply-splash-core/ply-device-manager.h
@@ -31,7 +31,8 @@ typedef enum
 {
         PLY_DEVICE_MANAGER_FLAGS_NONE = 0,
         PLY_DEVICE_MANAGER_FLAGS_IGNORE_SERIAL_CONSOLES = 1 << 0,
-                PLY_DEVICE_MANAGER_FLAGS_IGNORE_UDEV = 1 << 1
+        PLY_DEVICE_MANAGER_FLAGS_IGNORE_UDEV = 1 << 1,
+        PLY_DEVICE_MANAGER_FLAGS_SKIP_RENDERERS = 1 << 2
 } ply_device_manager_flags_t;
 
 typedef struct _ply_device_manager ply_device_manager_t;
diff --git a/src/main.c b/src/main.c
index f1e0fa7c..841fe6b2 100644
--- a/src/main.c
+++ b/src/main.c
@@ -2358,7 +2358,9 @@ main (int    argc,
                 device_manager_flags |= PLY_DEVICE_MANAGER_FLAGS_IGNORE_UDEV;
 
         if (!plymouth_should_show_default_splash (&state)) {
-                /* don't bother listening for udev events if we're forcing details */
+                /* don't bother listening for udev events or setting up a graphical renderer
+                 * if we're forcing details */
+                device_manager_flags |= PLY_DEVICE_MANAGER_FLAGS_SKIP_RENDERERS;
                 device_manager_flags |= PLY_DEVICE_MANAGER_FLAGS_IGNORE_UDEV;
 
                 /* don't ever delay showing the detailed splash */